This invention relates generally to an apparatus for removing moisture from a hot compressed gas, and more particularly to such an apparatus which is particularly adapted for use with an air compressor which supplies compressed air to a separate work tool, such as a sand blast apparatus, for example.
It has long been recognized that it is desirable to dehumidify hot compressed gas leaving a compressor prior to the compressed air reaching an object of interest, such as a work tool. In this regard, prior dehumidification systems typically employ an aftercooler, which may be cooled by ambient air or a refrigeration system, and a water separator positioned to remove any condensed water from the cooled airstream. However, the use of an aftercooler leaves the possibility of condensation developing in the downstream piping, since the aftercooler typically supplies saturated compressed air at a temperature slightly above the ambient temperature. Therefore, any further cooling will result in further condensation formation, which may interfere with the operation of a downstream work tool or process. For example, in abrasive blasting, such as sand blasting, the presence of moisture in the compressed air flow to the work tool causes the abrasive mixture to clog and cake which reduces the efficiency of the abrasive blasting process.
It also has been proposed, especially with systems having long piping runs, to use a recuperator type heat exchanger to reheat the compressed air after it exits the aftercooler and drops its condensation. The recuperator takes the form of a separate heat exchanger located in conjunction with the aftercooler. This, however, results in a cumbersome configuration having two hoses between the aftercooler and the recuperator. Also, additional piping is required from the compressor to the recuperator and from the recuperator to the work tool being served with the dry compressed air. This known arrangement can become even more unwieldy if the water separator is mounted between the aftercooler outlet and the recuperator. With the required piping and large number of connections, the pressure drop of the compressed air, and the likelihood of leaks, is increased. Further, it is common for users to mismatch the size, flow rates, and power of the aftercooler and the recuperator, and to even reverse their proper order in the system.
The foregoing illustrates limitations known to exist in present dehumidification systems. Thus, it is apparent that it would be advantageous to provide an alternative directed to overcoming one or more of the limitations set forth above. Accordingly, a suitable alternative is provided including features more fully disclosed hereinafter.